/* 91PO Official Site — Midnight Velvet Theme */
:root {
  --bg-deep: #06060c;
  --bg-card: #0f0f1a;
  --bg-elevated: #161625;
  --accent-orange: #ff6b00;
  --accent-gold: #e8a838;
  --accent-purple: #9d4edd;
  --accent-pink: #e040a0;
  --accent-blue: #5b8def;
  --text-primary: #f2f0f5;
  --text-secondary: #9a96a8;
  --text-muted: #5c5868;
  --border-subtle: rgba(255, 107, 0, 0.12);
  --glow-orange: rgba(255, 107, 0, 0.35);
  --glow-purple: rgba(157, 78, 221, 0.25);
  --nav-height: 60px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg-deep);
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 15px;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 20% -10%, var(--glow-purple) 0%, transparent 55%),
    radial-gradient(ellipse 60% 40% at 85% 110%, var(--glow-orange) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--accent-orange);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--accent-gold);
}

ul, ol {
  padding-left: 1.4em;
}

h1, h2, h3, h4 {
  line-height: 1.35;
  font-weight: 700;
}

h1 { font-size: clamp(1.6rem, 5vw, 2.4rem); }
h2 { font-size: clamp(1.3rem, 4vw, 1.75rem); margin-bottom: 1rem; }
h3 { font-size: 1.15rem; margin-bottom: 0.75rem; }

p { margin-bottom: 1rem; }

.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 18px;
  position: relative;
  z-index: 1;
}

/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(6, 6, 12, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  z-index: 1000;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 18px;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-link img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
}

.logo-text {
  font-size: 1.15rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent-orange), var(--accent-gold));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: 0.02em;
}

.nav-desktop {
  display: none;
  gap: 28px;
  list-style: none;
  padding: 0;
}

.nav-desktop a {
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  position: relative;
}

.nav-desktop a:hover,
.nav-desktop a.active {
  color: var(--text-primary);
}

.nav-desktop a.active::after {
  content: "";
  position: absolute;
  bottom: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 18px;
  height: 2px;
  background: var(--accent-orange);
  border-radius: 2px;
}

.menu-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

.menu-toggle.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

.nav-mobile {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  background: rgba(10, 10, 18, 0.97);
  backdrop-filter: blur(20px);
  padding: 16px 18px 24px;
  border-bottom: 1px solid var(--border-subtle);
  z-index: 999;
}

.nav-mobile.open { display: block; }

.nav-mobile ul {
  list-style: none;
  padding: 0;
}

.nav-mobile li {
  border-bottom: 1px solid rgba(255,255,255,0.05);
}

.nav-mobile a {
  display: block;
  padding: 14px 0;
  color: var(--text-secondary);
  font-size: 1rem;
}

.nav-mobile a:hover,
.nav-mobile a.active {
  color: var(--accent-orange);
}

@media (min-width: 768px) {
  .nav-desktop { display: flex; }
  .menu-toggle { display: none; }
}

/* ===== Ads ===== */
.ads-section {
  padding-top: calc(var(--nav-height) + 12px);
  padding-bottom: 8px;
}

.ads-sticky-bar {
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  z-index: 950;
  background: rgba(6, 6, 12, 0.94);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-subtle);
  padding: 8px 12px;
  transform: translateY(-100%);
  opacity: 0;
  visibility: hidden;
  transition: transform 0.3s ease, opacity 0.3s ease, visibility 0.3s;
}

.ads-sticky-bar.visible {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

.ads-wrapper {
  max-width: 1100px;
  margin: 0 auto;
}

.ads-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: flex-start;
  gap: 6px 4px;
}

.ads-grid > div {
  width: calc(25% - 4px);
  display: flex;
  flex-direction: column;
  align-items: center;
}

.ads-grid figure {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 0;
}

.ads-grid img {
  width: 58px;
  height: 58px;
  object-fit: cover;
  border-radius: 16px;
  box-shadow: 0 4px 14px rgba(0,0,0,0.35);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
  border: 1px solid rgba(255,107,0,0.15);
}

.ads-grid a {
  display: inline-block;
  border-radius: 16px;
}

.ads-grid img:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 8px 20px var(--glow-orange);
}

.ads-grid .caption {
  height: 15px;
  font-size: 10px;
  color: var(--text-muted);
  text-align: center;
  max-width: 72px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  margin-top: 3px;
}

@media (min-width: 768px) {
  .ads-grid > div { width: calc(12.5% - 4px); }
  .ads-grid img { width: 62px; height: 62px; }
}

/* ===== Hero ===== */
.hero {
  padding: 48px 0 56px;
  text-align: center;
  position: relative;
}

.hero-badge {
  display: inline-block;
  padding: 5px 16px;
  background: rgba(157, 78, 221, 0.15);
  border: 1px solid rgba(157, 78, 221, 0.3);
  border-radius: 20px;
  font-size: 0.78rem;
  color: var(--accent-purple);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 20px;
}

.hero h1 {
  margin-bottom: 16px;
  background: linear-gradient(160deg, #fff 30%, var(--accent-orange) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  color: var(--text-secondary);
  font-size: 1.02rem;
  max-width: 640px;
  margin: 0 auto 28px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  list-style: none;
  padding: 0;
}

.hero-tags li {
  padding: 6px 14px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  color: var(--text-secondary);
}

/* ===== Content Blocks (3:7 ratio) ===== */
.section {
  padding: 48px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 36px;
}

.section-header p {
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

.content-block {
  display: grid;
  grid-template-columns: 3fr 7fr;
  gap: 28px;
  align-items: start;
  margin-bottom: 40px;
  padding: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
}

.content-block.reverse {
  grid-template-columns: 7fr 3fr;
}

.content-block.reverse .block-image { order: 2; }
.content-block.reverse .block-text { order: 1; }

.block-image {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 8px 32px rgba(0,0,0,0.4);
}

.block-image img {
  width: 100%;
  border-radius: var(--radius-md);
}

.block-image::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-md);
  border: 1px solid rgba(255,107,0,0.2);
  pointer-events: none;
}

.block-text h3 {
  color: var(--accent-gold);
}

.block-text p {
  color: var(--text-secondary);
  font-size: 0.94rem;
}

.block-text ul {
  color: var(--text-secondary);
  font-size: 0.92rem;
  margin-bottom: 1rem;
}

.block-text ul li { margin-bottom: 6px; }

@media (max-width: 767px) {
  .content-block,
  .content-block.reverse {
    grid-template-columns: 1fr;
  }
  .content-block.reverse .block-image,
  .content-block.reverse .block-text { order: unset; }
}

/* ===== Feature Grid ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 32px;
}

.feature-card {
  padding: 22px 18px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: border-color var(--transition), transform var(--transition);
}

.feature-card:hover {
  border-color: rgba(255,107,0,0.35);
  transform: translateY(-2px);
}

.feature-icon {
  font-size: 1.5rem;
  margin-bottom: 10px;
}

.feature-card h4 {
  font-size: 0.95rem;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 0;
  line-height: 1.6;
}

@media (min-width: 768px) {
  .feature-grid { grid-template-columns: repeat(4, 1fr); }
}

/* ===== CTA ===== */
.cta-section {
  padding: 56px 0;
  text-align: center;
}

.cta-box {
  padding: 40px 28px;
  background: linear-gradient(145deg, rgba(255,107,0,0.08), rgba(157,78,221,0.08));
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
}

.cta-box h2 { margin-bottom: 12px; }

.cta-box p {
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto 24px;
}

.btn-primary {
  display: inline-block;
  padding: 14px 36px;
  background: linear-gradient(135deg, var(--accent-orange), #ff8c33);
  color: #fff;
  border-radius: 28px;
  font-weight: 600;
  font-size: 0.95rem;
  box-shadow: 0 6px 24px var(--glow-orange);
  transition: transform var(--transition), box-shadow var(--transition);
}

.btn-primary:hover {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 10px 32px var(--glow-orange);
}

/* ===== Text-only SEO Section ===== */
.text-section {
  padding: 40px 0;
}

.text-panel {
  padding: 32px 28px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
}

.text-panel h2 {
  color: var(--accent-orange);
  margin-bottom: 20px;
}

.text-panel p,
.text-panel li {
  color: var(--text-secondary);
  font-size: 0.93rem;
}

.text-panel ul { margin-bottom: 1rem; }

/* ===== FAQ ===== */
.faq-list {
  list-style: none;
  padding: 0;
}

.faq-list li {
  padding: 18px 0;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.faq-list li:last-child { border-bottom: none; }

.faq-list h3 {
  font-size: 0.98rem;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.faq-list p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin: 0;
}

/* ===== Showcase Grid ===== */
.showcase-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin: 28px 0;
}

.showcase-item {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
}

.showcase-item img {
  width: 100%;
  aspect-ratio: 9/16;
  object-fit: cover;
}

.showcase-item figcaption {
  padding: 10px 12px;
  font-size: 0.78rem;
  color: var(--text-muted);
  line-height: 1.5;
}

@media (min-width: 768px) {
  .showcase-grid { grid-template-columns: repeat(4, 1fr); }
}

/* ===== Breadcrumb ===== */
.breadcrumb {
  padding-top: calc(var(--nav-height) + 20px);
  padding-bottom: 12px;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.breadcrumb a { color: var(--text-secondary); }
.breadcrumb span { color: var(--accent-orange); }

/* ===== Subpage ===== */
.page-content {
  padding: 24px 0 60px;
}

.page-content h1 {
  margin-bottom: 24px;
  font-size: clamp(1.4rem, 4vw, 2rem);
}

.page-content h2 {
  font-size: 1.2rem;
  color: var(--accent-gold);
  margin-top: 28px;
  margin-bottom: 12px;
}

.page-content p,
.page-content li {
  color: var(--text-secondary);
  font-size: 0.93rem;
}

.page-content ul,
.page-content ol {
  margin-bottom: 1rem;
}

/* ===== Error Pages ===== */
.error-page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.error-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 18px 60px;
}

.error-code {
  font-size: clamp(4rem, 15vw, 7rem);
  font-weight: 900;
  background: linear-gradient(135deg, var(--accent-purple), var(--accent-orange));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 16px;
}

.error-content h1 {
  margin-bottom: 12px;
}

.error-content p {
  color: var(--text-secondary);
  max-width: 420px;
  margin-bottom: 28px;
}

/* ===== Footer ===== */
.site-footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border-subtle);
  padding: 40px 0 28px;
  margin-top: 20px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

.footer-brand img {
  width: 44px;
  border-radius: 10px;
  margin-bottom: 12px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.85rem;
  max-width: 280px;
}

.footer-links h4 {
  font-size: 0.88rem;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.footer-links ul {
  list-style: none;
  padding: 0;
}

.footer-links li { margin-bottom: 8px; }

.footer-links a {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-links a:hover { color: var(--accent-orange); }

.footer-bottom {
  padding-top: 20px;
  border-top: 1px solid rgba(255,255,255,0.05);
  text-align: center;
  color: var(--text-muted);
  font-size: 0.78rem;
}

@media (min-width: 768px) {
  .footer-grid { grid-template-columns: 2fr 1fr 1fr; }
}